Drafting instrument



l. J. RICKEY DRAFTING INSTRUMENT Filed Dec.

Feb. 13, 1962 me 'RV'N J ATTORNEY FIG.7

nite States @a 3,920,642 Patented Feb. 13, 1962 aina-.ce

3,620,642 DRAFIING INSTRUMENT Irvin J. Rickey, 1013 SW. 30th, OklahomaCity, Okla. Filed Dee. 14, 1959, Ser. No. 859,205 4 Claims. (Cl. 33-93)The present invention relates to drawing tools and more particularly toa drafting instrument.

In structural drawing, it is frequently necessary to draw numerousparallel lines at selected angular positions with respect to a base lineor reference position as well as a plurality of arcs to different radii,as for example, when detailing beams and channel members on thestructural drawing.

It is, therefore, the principal object of the instant invention toprovide a draftsmans triangle with an adjustable swinging arm or bladewhich may be selectively positioned at any angle and pivoted about itsconnection with the triangle.

Another object is to provide a conventional drafting triangle with asliding bar which may be adjustably positioned along one side of thetriangle and to which the swinging blade is pivotally connected.

A further object is to provide a sliding bar means having a swingingblade pivotally connected thereto wherein the bar may be removablyconnected to opposing side portions of a drafting triangle.

Another object is to provide a device of this class wherein the swingingblade is provided with a series of progressively spaced-apart aperturesthroughout its length, for forming a like series of arcs originating atthe pivotal connection of the arm.

A further object is to provide a preferably transparent draftinginstrument which will perform a lwide variety of functions in draftingwork, such as drawing parallel lines, radii to a common or differentcenters, and arcs from a common or a plurality of centers.

Still another object is to provide a drafting instrument which will notimpair the use of the conventional triangle, forming a part of thecombination, when used separately.

The present invention accomplishes these and other objects by providinga drafting triangle and forming an elongated slot in spaced parallelrelation with respect to the hypotenuse side edge of the triangle.Sliding bar means is connected to one surface of the triangle throughthe slot and extends outwardly of the hypotenuse edge in right angularrelation thereto. An elongated substantially rectangular arm or blade ispivotally connected at one end to the free end of the bar. Intermediateits ends, the bar is provided with guide means and an upstanding wallfor contacting the adjacent edge or edges of the triangle and iixing theposition of the bar relative to the triangle. y

Other objects will be apparent from the following description when takenin conjunction with the accompanying single sheet of drawings, wherein:

FIGURE 1 is a plan view of the device illustrating, by dotted lines,various positions of the bar and swinging blade;

FIGURE 2 is a vertical cross-sectional view taken substantially alongthe line 2--2 of FIG. l;

FIGURE 3 is a fragmentary plan view of an alternate position of the bar;

FIGURE 4 is a plan view of the swinging blade, per se, illustrating aseries of longitudinally spaced-apart apertures therethrough;

FIGURE 5 is a view, similar to FIG. 4, illustrating an alternatearrangement or spacing of the series of apertures; and,

FIGURES 6 and 7 are vertical cross-sectional views taken substantiallyalong the lines 6-5 and 7--7 of FIG. 5, respectively.

Like characters of reference designate like parts in those figures ofthe drawings in which they occur.

In the drawings:

The reference numeral 1t) indicates the device, as a whole, whichincludes a conventional transparent triangle l2 having a pair of arms 14and 16 integrally joined to form a right angular corner portion 18, anda third arm 20, opposite the right angular corner, integrally joined tothe arms 14 and 16 and forming the hypotenuse of the triangle. Thetriangle i2 is illustrated as a 45 triangle but which may be a 60-90triangle or of other triangular shapes, if desired, but preferablyhaving at least one corner. An elongated relatively narrow slot 22 isformed through the arm 20 in spaced parallel relation with respect tothe hypotenuse edge 24 of the triangle. The undersurface 26 of thetriangle is recessed on opposing sides of the slot, as at 23, forrecessing the head portion 30 of a bolt 32 extending transversely of thetriangle through the slot 22.

A flat substantially rectangular bar 34 is flatly positioned upon theupper surface of the triangle and is provided with an aperture 36,adjacent one end, for receiving the upwardly disposed end of the bolt 32to which a knurled nut 38 is threadedly connected. A washer 40 isinterposed between the nut 38 and the upper surface 42 of the bar 34 sothat the nut 38 may be easily loosened or tightened for slidablypositioning the bar at selected positions along the slot 22. A guidemember 44, integral vvith the bar, extends transversely of the bar independing relation and has one Side edge 46 in contiguous contact withthe hypotenuse edge 24 for maintaining the bar 34 perpendicular withrespect to the hypotenuse of the triangle. The free end of the barprojects beyond the hypotenuse edge 24 a selected distance and is formedsemi-circular, as at 48, and is provided with -a central verticalopening 5t). One surface of the arcuate end of the bar is marked orscored with radial lines 49, spaced 15 apart, indicating degrees for thepurpose more fully explained hereinbelow.

An elongated substantially rectangular arm or blade 52, substantiallyequal in thickness to the thickness of the triangle l2, is provided witha transparent stud bolt 54 adjacent one of its ends. The bolt 54 isiixed at one end within the blade and projects outwardly of the opposingsurface a selected distance. The bolt 54 is closely received by theopening 50 and is held therein -by a knurled nut 56. The end portion ofthe blade 52, adjacent the bolt 54, is arcuately curved to describe asemicircular end 58 for cooperation with the semi-circular end 48 of thebar. One surface, preferably the lower surface, of the blade iscentrally scribed or scored longitudinally, as at 60, and a secondtransverse score line or mark '62 intersects the mark 6i? at the centerof the bolt 54. This permits manually loosening the nut 56 and alignedlypositioning the lines 60 and 62 with selected ones of the degree marks49 on the semi-circular end 48 of the bar. Throughout its length theblade 52 is provided with a series of apertures 64 which areprogressively spaced outward from the center of the bolt 54 beginning ata distance of approximately 2 inches therefrom and being longitudinallyspaced-apart in increments of a 1/16 of an inch and terminating 8 inchesfrom the bolt. The apertures at one side ofthe longitudinal center lineof the blade are spaced apart l/lf; of an inch while those on theopposing side of the center line read or are spaced at 1/8 inchintervals. Obviously the inch or fractions thereof may be marked on theblade. As shown in FIG. 2 the blade lies in the plane of the triangle.

FIG. 5 illustrates an alternate manner of arranging the spacing andpositioning of the apertures as indicated at 64A. Obviously theseapertures 64 and 64A may be arranged in any desired pattern and spacingfor achieving the desired arcs of different radii to be drawn by theblade. Each of the apertures are formed, as shown in FIG. 7, whereineach aperture has walls 65 converging downwardly terminating in arelatively small cylindrical end portion 66 opening to the underside ofthe blade and of a size for closely nesting the lead of a pencil or thelike.

The upper surface of the bar 34 is provided with an opstanding wall 70defining a right angular corner 72. The height of the wall issubstantially equal to the thickness of the triangle, as may be seen inFIG. 2. The blade 52 may be disconnected from the bar 34 and the bar maybe disconnected from the hypotenuse side of the triangle and invertedand connected to the right angular corner of the triangle through asuitable aperture 71 by the bolt 32 and nut 38. The inwardly disposedsurface of the wall 70 cooperatively contacts the outwardly disposededges of the arms 14 and 16, adjacent their juncture, thus firmlysecuring the bar 34 to the triangle (FIG. 3). The blade 52 is thensimilarly connected to the downwardly disposed surface of the free end4S of the bar. This places the blade 52 in the plane of the triangle.Selected side edges of the triangle may be scored or marked withincrements of the measurement as at 7S.

Operation ln operation, a selected side edge of the triangle arm 14 or16 is placed in contiguous contact with the edge of a parallel rule orT-square and with the bar connected to the slot 22 the blade 52 issecured in a selected angular position. A line may then be drawn withone side of the blade as a guide and other lines parallel to this linemay then be drawn by simply manually sliding the bar along thehypotenuse side of the triangle in the preferred direction. Similarlythe bar may `be selectively positioned on the triangle and the nut 56loosened whereby a pencil or the like may be inserted into the selectedapertures 64 or 64A for drawing a plurality of arcs from a commoncenter. As shown in FIG. l, with the bar connected to the hypotenuseside of the triangle, the blade 52 may be pivoted through an angularrange of 180.

Operation of the device when the bar 34 is connected to the rightangular corner of the triangle is similar to the above descriptionexcept, that, obviously the hypotenuse edge 24 forms the base line. Inthis arrangement, as shown by the dotted lines in FIG. l, the blade 52may be pivoted through a range of 276.

Obviously the invention is susceptible to some change or alterationwithout defeating its practicability, and l therefore do not wish to beconfined to the preferred embodiment shown in the drawings and describedherein, further than I am limited by the scope of the appended ciaims.

I claim:

l. A drafting instrument, comprising: a draftsmans triangle having sidesdefining a right angle corner, said triangle having an aperture adjacentsaid right angular corner; a relatively short substantially rectangularbar fiatly connected by one end portion to the upwardly disposed surfaceof said triangle through the aperture therein, the free end portion ofsaid bar projecting beyond said right angular corner; an outstandingwail carried intermediate its ends by said bar forming a right angularcorner in contiguous contact with the end portions of the sides of saidtriangle forming the right angular corner for preventing lateralmovement of said bar relative to said triangle, the free end portion ofsaid bar having a semi-circular edge and having a central aperturecoaxial with the semi-circular edge, at least one surface of thesemi-circular edge of said bar being scored to indicate radialmeasurements; an elongated blade pivotally connected at one end to thefree end portion of said bar, said blade having parallel opposing sideedges and having at least one surface of its pivotally connected endprovided with at least one score for co-operative registration with theradial scores in said one surface of said bar for fixing said blade atpredetermined angular positions relative to said triangle and said bar;and means for releasably securing said blade in such positions.

2. A drafting instrument, comprising: a draftsmans triangle having apair of arms integrally joined to form a right angular corner and havinga third arm integral with the end of said pair of arms forming ahypotenuse side edge, said triangle having a transverse apertureadjacent the right angular corner equally spaced between the side edgesforming said right angular corner; a substantially rectangular` flat baroverlying the right angle corner and removably connected atly by one endportion to the adjacent surface of said triangle through the aperturetherein, the free end portion of said bar projecting beyond said rightangular corner in perpendicular relation with respect to said hypotenuscedge, said bar having a semi-circular free end edge and having anaperture coaxial with the semi-circular edge, at least one surface ofthe semi-circular edge of said bar having a series of radially scoredindicia; an outwardly projecting wall formed intermediate the ends ofsaid bar on that side surface in contact with said triangle, saidoutstanding wall forming a right angular corner in contiguous contactwith the side edges of said triangle `forming said right angular corner;an elongated blade pivotally connected at one end to the free endportion of said bar, said blade having parallel opposing side edges andhaving at least one surface of its pivotally connected end provided withat least one score for co-operative registration with the radial scoresin said one surface of said bar for fixing said blade at predeterminedangular positions relative to said triangle and said bar; and means forreleasably securing said blade in such positions.

3. A drafting instrument, comprising: a draftsmans triangle having apair of arms defining a right angular corner and having a third armforming a hypotenuse edge of said triangle, said triangle having atransverse aperture adjacent the right angular corner equally spacedbetween the said edges forming said right angular corner; asubstantially rectangular fiat bar overlying said triangle and removablyconnected flatly by one end portion to one surface of said trianglethrough the aperture therein, the free end portion of said barprojecting beyond said right angular corner in perpendicular relationwith respect to said hypotenuse edge, said bar having a centrally boredsemi-circular free end portion, at least one surface of thesemi-circular edge having a series of radially positioned scores; a wallconnected to said bar intermediate its ends to define a right angularrecess in contiguous contact with the right angular corner of saidtriangle, the height of said wall being substantially equal to thethickness of said triangle; an elongated blade pivotally connected atone end to the free end portion of said bar, said blade having parallelopposing side edges and having at least one surface of its pivotallyconnected end provided with at least one score for co-operativeregistration with the radial scores in said one surface of said bar forfixing said blade at predetermined angular positions relative to saidtriangle and said bar; and means for releasably securing said blade insuch positions.

4. A drafting instrument, comprising: a draftsmans triangle having apair of arms defining a right angular corner and having a third armforming a hypotenuse edge of said triangle, said triangle having atransverse aperture adjacent the right angular corner equally spacedbetween the said edges forming said right angular corner; asubstantially rectangular dat bar overlying said triangle and removablyconnected flatly by one end portion to one surface of said trianglethrough the aperture therein, the free end portion of said barprojecting beyond said right angular corner in perpendicular relationwith respect to said hypotenuse edge, said bar having a centrally boredsemi-circular free end portion, at least one surface of thesemi-circular edge having a series of radially positioned scores; anoutstanding wall connected to said bar intermediate its ends to dene aright angular recess in the plane of said triangle wit-h one surface ofsaid wall contiguously contacting the edges of the arms forming theright angular corner of said triangle, the height of said wall beingsubstantially equal to the thickness of said triangle; an elongatedblade pivotally connected at one end to the free end portion of saidbar, said blade lying in the plane of said triangle and beingsubstantially equal with respect to the thickness of said triangle, saidblade having parallel opposing side edges and having at least onesurface of its pivotally connected end provided with 15 218931126 atleast one score for co-operative registration with the radial scores insaid one surface of said bar for xing said blade at predeterminedangular positions relative to said triangle and said bar; and means forreleasably securing said blade in such positions.

References Cited in the ile of this patent UNITED STATES PATENTS 738,130Waymire Sept. 1, 1903 765,300 Williams July 19, 1904 1,142,368 Row June8, 1915 1,336,241 La May Apr. 6, 1920 Coallier July 7, 1959

